Medical diagnostic apparatus, such as the SureTemp® thermometer manufactured and sold by Welch Allyn of Skaneateles Falls, N.Y., are known for measuring the body temperature of a patient. A probe includes a proximal end that is connected by means of a tethering cord to a device housing, the latter containing a processor and a display. The probe is defined by an elongate probe body, including a conically shaped distal probe tip that is configured to retain a temperature sensor or sensing element, as well as a heating element. The heating element is used in order to preheat the probe given the temperature differences between the environment and the core body temperature of a patient at an intended target (e.g., the axilla, rectum, sublingual pocket), so as to effectively shorten the amount of time that is required to take a temperature measurement.
A probe 14 of a prior art thermometry apparatus 10 is illustrated in FIGS. 1 and 2. As noted, the probe 14 includes a distal probe tip 18, the latter being defined by a substantially conical shape including a hollow interior. The heating element, such as an electrical resistor 24, is secured by epoxy along one circumferential portion of an interior wall 20 of the distal probe tip 18 and the temperature sensing element, such as a thermistor 28, is also attached using an epoxy or suitable adhesive along another circumferential portion of the interior wall 20, each of the heating element and temperature sensing element being adjacent to the distal end 19 of the distal probe tip 18. Sets of electrical leads 32, 34, in the form of low gauge copper wires, extend proximally from each of the resistor 24 and thermistor 28, respectively, and further extend through the body of the probe 14 to a connector on the proximal end (not shown) of the probe 14 for attachment to the device housing (not shown). The electrical leads 32, 34 provide electrical power to the retained components 24, 28 and also permit the transmission of signals from the temperature sensing element to the attached device housing (not shown) for processing and display, such as in the course of a typical patient examination.
As shown more clearly in FIG. 2 and during the normal course of use of this thermometry apparatus 100, the electrical leads 32, 34 extend away from the interior wall mounted components 24, 28 with little additional support, especially at the mounted ends of the leads 32, 34, and are therefore susceptible to breakage. Premature breakage of the electrical leads 32, 34 frequently requires a complete replacement of the entire thermometry probe 14, and not just the interior components.
Based in part on the foregoing, there is a general and ongoing need to improve the durability and manufacturability of thermometry assemblies, so as to improve their reliability and increase working life.
Because the temperature sensing element and the heating element are eccentrically mounted to the interior wall of the probe tip, there may also be inconsistencies in terms of heat generation and detection. As a result, there is another general need to improve these characteristics in a thermometry apparatus.